Extendable articulated probe device

ABSTRACT

An articulate probe device includes a first mechanism, a second mechanism, and an overtube mechanism. The first mechanism includes a proximal link which is movable coupled to a first intermediate link, a plurality or intermediate links, and a distal link which is moveably coupled to a second one of the intermediate links. The second mechanism includes a proximal link which is movable coupled to a first intermediate link, a plurality of intermediate links, and a distal link which is moveably coupled to a second one of the intermediate links. The overtube mechanism includes a proximal link which is movable coupled to a first intermediate link, a plurality of intermediate links, and a proximal link which is moveably coupled to a second one of the intermediate links. Further, at least one of the first mechanism, second mechanism, and overtube mechanism is steerable and extendable beyond the other mechanisms.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the filing date of, and priorityto, U.S. Provisional Patent Application No. 61/059,171 filed Jun. 5,2008.

BACKGROUND

This application discloses an invention that is related, generally andin various embodiments, to a multi-linked robotic device, a continuumrobot, or other highly articulated device. This device may be used todeliver a tool such as a camera, probe, scalpel or other tool to an areaof interest inside a patient's body during a surgical procedure. Forminimally invasive procedures, such as cardiac ablation, a minimallycomplex articulated device is usually sufficient. However, for morecomplex procedures, a longer device may be necessary. A longer mechanismmay require extra support along at least a portion of its length tocounteract any increased loading. In addition, the device may need toaccommodate additional tools needed to perform certain parts of a morecomplex procedure.

SUMMARY

Before the present methods are described, it is to be understood thatthis invention is not limited to the particular systems, methodologiesor protocols described, as these may vary. It is also to be understoodthat the terminology used herein is for the purpose of describingparticular embodiments only, and is not intended to limit the scope ofthe present disclosure which will be limited only by the appendedclaims.

It must be noted that as used herein and in the appended claims, thesingular forms “a.” “an,” and “the” include plural reference unless thecontext clearly dictates otherwise. Unless defined otherwise, alltechnical and scientific terms used herein have the same meanings ascommonly understood by one of ordinary skill in the art. As used herein,the term “comprising” means “including, but not limited to.”

In one general respect, the embodiments disclose an articulated probedevice. The articulate probe device includes a first mechanism, a secondmechanism, and at least one overtube mechanism. More specifically, thefirst mechanism includes a first link positioned at a proximal area ofthe first mechanism, a plurality of intermediate links, wherein a firstone of the intermediate links is moveably coupled to the first link, anda second link positioned at a distal area of the second mechanism whichis moveably coupled to a second one of the intermediate links. Thesecond mechanism includes a first link positioned at a proximal area ofthe second mechanism, a plurality of intermediate links, wherein a firstone of the intermediate links is moveably coupled to the first link, anda second link positioned at a distal area of the second mechanism andwhich is moveably coupled to a second one of the intermediate links. Theat least one overtube includes a first link positioned at a proximalarea of the overtube mechanism, a plurality of intermediate links,wherein a first one of the intermediate links is moveably coupled to thefirst link, and a second link which is moveably coupled to a second oneof the intermediate links and positioned at a proximal area of theovertube mechanism. Further, at least one of the first mechanism, secondmechanism, and overtube mechanism is configured to be steerable andextendable beyond the other mechanisms.

BRIEF DESCRIPTION OF DRAWINGS

Various embodiments of the invention are described herein by way ofexample in conjunction with the following figures.

FIGS. 1 and 2 illustrate various embodiments of a steerable multi-linkeddevice.

FIG. 3 illustrates various embodiments of a core mechanism of the deviceof FIG. 1.

FIGS. 4 and 5 illustrate various embodiments of an intermediate link ofthe core mechanism.

FIG. 6 illustrates various embodiments of a motion sequence of thedevice of FIG. 1.

FIG. 7 illustrates an exemplary cross-section of an overtube accordingto an embodiment.

FIG. 8 illustrates an exemplary steerable multi-linked device having anovertube according to an embodiment.

FIGS. 9A-9C illustrates exemplary cross-sections of a steerablemulti-linked device having an overtube according to an embodiment.

FIG. 10 illustrates exemplary steerable multi-linked devices having anovertube according to an embodiment.

FIG. 11 illustrates an exemplary cross-section of a steerablemulti-linked device according to an embodiment.

FIG. 12 illustrates an exemplary tensioning cables and splice accordingto an embodiment.

FIG. 13A-13J illustrate exemplary port and through-hole configurationsare according to an embodiment.

DETAILED DESCRIPTION

It is to be understood that at least some of the figures anddescriptions of the invention have been simplified to focus on elementsthat are relevant for a clear understanding of the invention, whileeliminating, for purposes of clarity, other elements that those ofordinary skill in the an will appreciate may also comprise a portion ofthe invention. However, because such elements are well known in the art,and because they do not necessarily facilitate a better understanding ofthe invention, a description of such elements is not provided herein.

According to various embodiments, the invention described herein may beutilized to control movement of an articulated device, which in thefigures and description herein is described as a steerable multi-linkeddevice. In an embodiment, a surgical probe may be an exemplaryarticulated device. A surgical probe may be used to perform surgicalprocedures, exploratory procedures and/or the like on humans and/oranimals. For ease of explanation purposes, the invention will bedescribed in the context of its use with various embodiments of thesteerable multi-linked device described herein. However, one skilled inthe an will appreciate that the invention may be utilized with othertypes of multi-linked devices as well as other types of devices such as,but not limited to, endoscopes, highly articulated devices and/or thelike.

FIG. 1 illustrates a representative embodiment of a highly articulatedextendible probe device 10. The cross-section of such an embodiment isdepicted in FIG. 1. According to the representative embodiment, thedevice may be a steerable multi-linked device such as a snake-likerobot, a continuum robot or the like. Various embodiments of the device10 may be utilized for medical procedures (e.g., as a robotic bore,positioning device, ablation tool, camera or instrument support, orguidance system for minimally invasive procedures), for surveillanceapplications, for inspection applications, for search and rescueapplications, etc. For purposes of clarity only, the utility of thedevice 10 will be described hereinbelow in the context of itsapplicability to medical procedures. However, a person skilled in the anwill appreciate that the device 10 can be utilized in a variety ofdifferent applications.

The device 10 comprises a first mechanism 12 and a second mechanism 14.According to the representative embodiment, a mechanism may be a seriesof articulated links, a snake-like robot, a continuum robot or the like.According to the representative embodiment, the second mechanism 14 isstructured and arranged to receive and surround the first mechanism 12as shown in FIG. 2. Thus, the first mechanism and second mechanism maybe concentric. According to other embodiments, the first and secondmechanisms 12, 14 may be structured and arranged to have a relationshipother than a concentric relationship. For example, the second mechanism14 may surround the first mechanism 12, however, the first mechanism 12may be arranged eccentrically with respect to the second mechanism 14.According to the representative embodiment, the first and secondmechanisms 12, 14 may be structured and arranged to operate in aside-by-side arrangement, where the first mechanism 12 operatesalongside the second mechanism 14. According to the representativeembodiment, additional and/or alternate configurations may be usedwithin the scope of this disclosure. According to the representativeembodiment, a gap or three-dimensional space 240 may be provided betweenthe first and second mechanisms. This space will be described in moredetail below.

As described in more detail hereinbelow, the first mechanism 12 mayoperate in either a rigid mode or a limp mode, the second mechanism 14may operate in either a rigid mode or a limp mode, and the first andsecond mechanisms 12, 14 may operate independent of one another. Atleast one of the mechanism is rigid at all times during operation of thedevice 10. Both the first mechanism 12 and the second mechanism 14 maybe steerable mechanisms. Accordingly, it will be appreciated that thedevice 10 may be utilized to navigate a luminal space as well as anypath within a three-dimensional intracavity space, void, or an otherwiseunconstrained three dimensional volume. According to the representativeembodiment, the device 10 may advance by alternating the operation ofthe first mechanism 12 and the second mechanism 14 between a limp modeand a rigid mode. Further, both mechanisms can both exist in the rigidmode at the same time.

According to the representative embodiment, the device 10 may alsocomprise one or more cables. According to the representative embodiment,one or more of the cables 10 may be steering cables and/or tensioningcables. For example, the device 10 may include three cables for steeringdisposed through the second mechanism and one cable for tensioning whichis disposed through the first mechanism. Alternatively, the device 10may include four steering cables. More, fewer, alternative and/oradditional cables may be used within the scope of this disclosure.

FIG. 3 illustrates various embodiments of either mechanism of thedevice. Shown in FIG. 3 is the first mechanism 12 of the device 10. Thefirst mechanism 12 is a multi-linked mechanism and includes a first end24 and a second end 26. The first end 24 may be considered the proximalend and the second end 26 may be considered the distal end. The firstmechanism 12 may comprise a first link 28, a second link 30, and one ormore intermediate links 32 between the first and second links 28, 30.The first link 28 may be considered the proximal link, and the secondlink 30 may be considered the distal link. Any link between the proximallink 28 and distal link 30 may be considered an intermediate link 32.Exemplar link structures are shown in, for example, U.S. PatentApplication Publication No. 200810039690.

FIGS. 4 and 5 illustrate various views of an exemplary intermediate link32 of the first mechanism 12 in an embodiment where the inner mechanismserves as the core. The intermediate link 32 is representative of theother intermediate links 32. The intermediate link 32 includes a firstend 58 and a second end 60, and defines a longitudinal axis 62 thatpasses through the center of the first end 58 and the center of thesecond end 60. Link 32 includes a passage 76 or through-hole which maybe positioned along the longitudinal axis, or it may be positionedelsewhere in the link parallel to, or substantially parallel to, thelongitudinal axis.

As shown in FIG. 4, the intermediate link 32 also comprises a firstsurface 68 that extends from the first end 58 of the intermediate link32 to the second end 60 of the intermediate link 32. The first surface68, shown in FIG. 5, may be considered the outer surface of theintermediate link 32. The intermediate link 32 also defines one or moreport portions, referred to herein as grooves. In the example shown, link32 includes a first groove 70 parallel to the longitudinal axis 62 alongthe first surface 68, a second groove 72 parallel to the longitudinalaxis 62 along the first surface 68, and a third groove 74 substantiallyaligned to the longitudinal axis 62 along the first surface 68. Each ofthe first, second and third grooves 70, 72, 74 extend along the firstsurface 68 from the first end 58 of the intermediate link 32 toward thesecond end 60 of the intermediate link 32. The first, second and thirdgrooves 70, 72, 74 may be semi-tubular shaped and may be arranged in aradially symmetric manner around the longitudinal axis 62 on the firstsurface 68 of the intermediate link 32 as shown in FIGS. 4 and 5. Thesize of each of the grooves 70, 72, 74 may be identical to one anotheror may be different from one another. For example, according to variousembodiments, the first and second grooves 70, 72 are configured assegments of a cylinder having a diameter on the order of approximately1.75 millimeters at the first end 58 of the intermediate link 32, andthe third groove 74 is configured as a segment of a cylinder having adiameter on the order of approximately 2.50 millimeters at the first end58 of the intermediate link 32. The first, second and third grooves 70,72, 74 are each configured to provide a portion of a port structure thatreceives and partially surrounds any of a variety of

The intermediate link 32 also defines a through-hole or passage 76extending from the first end 58 to the second end 60 and is parallel tothe longitudinal axis. The through-hole or passage 76 may be of a sizesufficient to allow one or more cables to pass there-through.

FIG. 6 illustrates various steps of a motion sequence of the steerablemulti-linked device 10. At the start of the sequence, the secondmechanism 14 surrounds the first mechanism 12 as shown in step “a” ofFIG. 6, the longitudinal axes of the links 28, 30, 32 of the firstmechanism 12 are substantially aligned with the respective longitudinalaxes 134, 164, 212 of the links (e.g. link 126) of the second mechanism,and the second end 26 of the first mechanism 12 is at substantially thesame position as the second end 122 of the second mechanism 14. Atensioning cable passes through a through-hole of the first mechanism.It is terminated on an actuation component at the proximal area or endof the first mechanism and at a next-to-last link at a distal end. Thetensioning cable is pulled tight, thereby placing at least a portion ofthe first mechanism 12 in the rigid mode by placing a force on thedistal link and at least a some intermediate links. The steering cablesare not pulled tight, thereby placing the second mechanism 14 in thelimp mode.

The second mechanism 14 is then advanced so that its second link 126 ispositioned approximately one link ahead of the second end 24 of thefirst mechanism 12 as shown in step “b” of FIG. 6. The cables 16, 18, 20may be utilized to orient the second link 126 to a particularorientation, where the longitudinal axis 134 of the first link 124 is nolonger aligned with the longitudinal axes 164 of the intermediate links128 of the second mechanism 14 or the longitudinal axis 90 of the secondlink 30 of the first mechanism 12. After the second link 126 is in thedesired position and orientation, the steering cables are pulled withappropriate forces in order to place the second mechanism 14 in therigid mode, thereby preserving the position and orientation of thesecond mechanism 14 when the first mechanism is made limp.

The pulling force of the tensioning cable is then released to place thefirst mechanism 12 in the limp mode. After the first mechanism 12 isplaced in the limp mode, the first mechanism 12 is advanced so that itssecond link 30 is at substantially the same position as the second end122 of the second mechanism 14 as shown in step “c” of FIG. 6. After thesecond link 30 of the first mechanism 12 is in the desired position, thetensioning cable is pulled tight to place the first mechanism 12 back inthe rigid mode, thereby preserving the position and orientation of thefirst mechanism 12.

The pulling forces of the steering cables are then released to place thesecond mechanism 14 back in the limp mode. After the second mechanism 14is placed back in the limp mode, the second mechanism 14 is advanced sothat its second link 126 is once again positioned approximately one linkahead of the second end 26 of the first mechanism 12 as shown in step“d” of FIG. 6. After the second link 126 is in the desired position andorientation, the steering cables are pulled with identical force inorder to place the second mechanism 14 in the rigid mode, therebypreserving the position and orientation of the second mechanism 14.

The pulling force of the tensioning cable is then released to place thefirst mechanism 12 back in the limp mode. After the first mechanism 12is placed back in the limp mode, the first mechanism 12 is advanced sothat its second link 30 is once again at substantially the same positionas the second end 122 of the second mechanism 14 as shown in step “e” ofFIG. 6. After the second link 30 of the first mechanism 12 is in thedesired position and orientation, the tensioning cable is pulled tightto place the first mechanism 12 back in the rigid mode, therebypreserving the position and orientation of the first mechanism

In an embodiment, the flexible, snake-like device 10 may include one ormore overtubes. In an embodiment, an overtube may include a series oflinks in a similar fashion to the second mechanism. In an embodiment, anovertube may be a snake-like robot, a continuum robot or the like. Anovertube may be fabricated from metal, plastic, fiber, reinforced fiber,any combination thereof and/or the like.

In an embodiment, an overtube may include one or more through-holes. Athrough-hole may extend along a length of the overtube. In anembodiment, a through-hole may be substantially cylindrically shaped. Athrough-hole may be configured to surround and receive a cable. Forexample, as illustrated by FIG. 13, a through-hole 1800 may receive asteering cable 1805. In an embodiment, a steering cable may assist incontrolling and guiding the movement of an overtube.

In an embodiment, an overtube 1820 may include one or more grooves, suchas the grooves described above with respect to the intermediate link 32.The grooves of an overtube may align with grooves on the outside of asecond mechanism to form one or more ports such as port 1900. A port maybe a passageway that extends along a length of a device. In anembodiment, an overtube may wholly contain one or more ports. In anembodiment, ports may be configured to surround and receive one or moretools. Additionally, overtube 1820 may include one or more through-holes1800. For example, FIG. 7 illustrates an exemplary through-hole 1905receiving a tensioning cable 1915 and an exemplary port 1900 receiving atool 1910.

In an embodiment, an overtube may surround both the first mechanism 12and the second mechanism 14. For example, as illustrated by FIGS. 9A-9C,the second mechanism 1405 may surround the first mechanism 1415, and theovertube 1400 may surround the second mechanism 1405. In an embodiment,as shown in FIG. 2, the first mechanism 12 may be positionedconcentrically with respect to the second mechanism 14. Alternatively,as shown in FIGS. 9A-9C, the first mechanism 1415 may be positionedeccentrically with respect to the second mechanism 1405. For example,the first mechanism 1415 may be located oft-center from the secondmechanism 1405. In an embodiment, the second mechanism 1405 may bepositioned concentrically with respect to the overtube 1400.Alternatively, the second mechanism 1405 may be positioned eccentricallywith respect to the overtube 1400. In an embodiment, the overtube may befabricated from plastic, such as polysulfone and/or the like.

In an embodiment, the first mechanism 1415 and the second mechanism 1405may be collectively considered an inner mechanism, and the overtube 1400may be considered an outer mechanism. In an embodiment, the device mayoperate in a first mode. The first mechanism 1415 and the secondmechanism 1405 may operate substantially in unison and both mechanismsmay alternate between a rigid and a limp state together. The operationof the first mechanism 1415 and second mechanism 1405 may becomplimentary to the overtube 1400. For example, the first mechanism1415 and the second mechanism 1405 may both be made limp while theovertube 1400 is made rigid. Alternatively, the first mechanism 1415 andthe second mechanism 1405 may both be made rigid when the overtube 1400is made limp. Still further, the all mechanism may be made rigid at thesame time.

For example, while in a limp state, the first mechanism 1415 and secondmechanism 1405 may advance into the overtube 1400 to a certain position.The first mechanism 1415 and the second mechanism 1405 may be maderigid, while the overtube 1400 may be made limp. The overtube 1400 mayadvance over the first mechanism 1415 and the second mechanism 1405.This motion sequence is analogous to the motion sequence describe aboveand depicted in FIG. 6.

In an embodiment, the device may operate in a second mode. In a secondmode, the overtube 1400 may act as a steerable cannula that may bepositioned with assistance from the first mechanism 1415 and the secondmechanism 1405. For example, after reaching a target location, theovertube 1400 may be made rigid. The first mechanism 1415 and secondmechanism 1405 may continue to advance, while the overtube 1400 mayremain stationary. As illustrated in FIG. 8, the overtube 1400 mayprovide additional length to the flexible, snake-like device 10,allowing for more flexibility in its positioning and use. The overtube1400 may also provide additional support to the first mechanism(contained within the second mechanism 1405) and the second mechanism1405. As illustrated by FIG. 7, the radius of curvature associated withan overtube 1400 may, in some embodiments, be at least as large as theradius of curvature associated with the second mechanism 1405

FIGS. 9A-9C illustrate exemplary cross-sections of an articulated devicehaving an overtube according to an embodiment. In FIG. 9A, across-section of an overtube 1400 is highlighted. As illustrated by FIG.9A, an overtube 1400 may include one or more through-holes 1401, 1402,1403. Steering cables used to control the overtube 1400 may be receivedby the through-holes 1401, 1402, 1403.

In FIG. 9B, a cross-section of a second mechanism 1405 is highlighted.As illustrated by FIG. 9B, a second mechanism 1405 may include one ormore through-holes 1408, 1409, 1410. Steering cables used to controlmovement of the second mechanism 1405 may be received by thethrough-holes 1408, 1409, 1410. In an embodiment, the second mechanism1405 may include one or more ports 1406, 1407. A port may be apassageway that extends along the length of a device. In an embodiment,a port may be formed by the alignment of one or more grooves of a firstmechanism and one or more grooves or walls of a second mechanism. In analternate embodiment shown in FIG. 9B, a port may be wholly formed in afirst mechanism and/or a second mechanism. In an embodiment, one or morethrough-holes may be configured to surround and receive one or moretensioning cables and at least one port may be configured to surroundtools and/or the like.

In FIG. 9C, a cross-section of the first mechanism 1415 is highlighted.As illustrated by FIG. 9C, a first device 1415 may include athrough-hole 1420 for delivery of a tool.

In an embodiment, an overtube may be used to deliver a plurality offlexible, snake-like devices 10 to a location as illustrated by FIG. 10.Although FIG. 10 illustrates an overtube surrounding two devices 1500,1505 in a parallel configuration, additional devices and/or alternateconfigurations may be used within the scope of this disclosure.

In an embodiment, each device may be operated in a first mode; such asthat described above. In an embodiment, each device may be operated insubstantial unison with each of the other devices. For example, while ina limp state, a first device 1500 and a second device 1505 may advanceinto the overtube 1510 to a certain position. The first device 1500 andthe second device 1505 may be made rigid, while the overtube 1510 may bemade limp. The overtube 1510 may advance over the first device 1500 andthe second device 1505.

In an embodiment, the devices 1510, 1505 and the overtube 1510 mayoperate in a second mode, similar to that described above. In anembodiment, the overtube 1510 may act as a steerable cannula that may bepositioned with assistance from the first device 1500 and the seconddevice 1505. For example, after reaching a target location, the overtube1510 may be made rigid. The first device 1500 and second device 1505 maycontinue to advance, while the overtube 1510 may remain stationary. Thefirst device 1500 and the second device 1505 may be independentlyoperated as they advance beyond the overtube 1310. The overtube 1310 mayprovide additional length to the flexible, snake-like device 10,providing for more flexibility in its positioning and use. The overtube1510 may also provide additional support to the first device 1500 andthe second device 1500.

In an embodiment, a plurality of overtubes arranged in a nestedstructure may be used in conjunction with one or more devices. FIG. 11illustrates a cross-section of the device having n-overtubes which arenested concentrically within each other according to an embodiment. Asillustrated by FIG. 11, overtube a 1600 may surround at least a portionof overtube n−1 1605. Overtube n−1 1605 may in turn surround at least aportion of overtube 4 1610, and so on. As illustrated by FIG. 11, with anested arrangement, either concentrically or eccentrically, ofn-overtubes, a device may have a telescopic configuration. Any of theovertubes may be steerable or non-steerable, and those which aresteerable will have a plurality of associate steering cables.Non-steerable devices require only a tensioning cable in a through-hole,and no steering cable. In an embodiment, the added support provided byadditional overtubes may allow a device to reach lengths it otherwisewould not be able to reach.

In an embodiment, a device may include one or more first mechanisms, oneor more second mechanisms and/or one or more overtubes. The firstmechanisms, second mechanisms and/or overtubes may be arranged in anested, parallel and/or in any other configuration or combination ofconfigurations. In an embodiment, one or more first mechanisms, secondmechanisms and/or overtubes may be arranged concentrically,eccentrically and/or the like. For example, a first mechanism may bepositioned concentrically relative to a second mechanism. Similarly, adevice may be positioned eccentrically relative to an overtube.

In an embodiment, when a first mechanism is disposed eccentricallyrelative to a second mechanism, the first mechanism may “break out” ofthe channel through which it disposed during advancement when the deviceis highly curved. To resolve this problem, a passive section of innerlinks may be added to a distal end of the first mechanism. FIG. 12illustrates an tensioning cable 1700 having a first cable portion 1705and a second cable portion 1720 spliced together. For example, a hollow,braided cable 1700 may be used. In an embodiment, the distal end of thebraided cable 1700 may be opened to form a sleeve 1715, and a shorter,separate section of the same type of cable may be inserted into the openweave of the sleeve 1715 as illustrated by FIG. 12. An active section ofcable 1720 and a passive section 1705 may be combined such that theirlongitudinal axes are substantially aligned. After a portion of theshorter segment is inserted into the open braid of the longer cable, atleast one running stitch 1710 may be run through both cables in thesection where they overlap. In an embodiment, the portion may beapproximately 3-5 mm long. In an embodiment, the stitch may secure thecables together.

In an embodiment, the increased diameter of the longer cable with theshorter cabled spliced into it may act as a force transmission point forthe cable of the first mechanism on one of the intermediate links. Theshorter section of cable may then hive one or more links strung onto it.In an embodiment, three to five links may be strung onto the shortersection of cable. In an embodiment, the passive links may be securedwith a stopper knot terminating the distal most end at the second link.Because the links of the active portion of the first mechanism may besecured between the feeder and the splice point, the intermediate linksthat are strung on the shorter section beyond the splice point may notbe subject to the same loads. As such, these intermediate links may notbecome rigid.

In an embodiment, an additional benefit of having the cable spliced maybe increased cable strength. For example, with a 150 lb test cable, thecable may break close to the knot at approximately 60 Lbs. With asplice, however, the cable may break far from the termination point atapproximately 100 lbs.

In an embodiment, a first mechanism, a second mechanism and/or anovertube may have any number of ports, through-holes and/or the like. Inan embodiment, the ports and/or through-holes may be arranged such thatthey are radially symmetric, radially asymmetric and/or the like.

In an embodiment, placement of ports and/or through-holes relative tothe first mechanism 12 and/or the second mechanism 14 may vary. Forexample, one or more ports may be placed concentrically or eccentricallyon the device 10. In addition, one or more ports may be fully containedwithin one or more mechanisms of the device 10. For example, one or moreports may be fully contained within the second mechanism 14. Similarly,one or more ports may be fully contained within the first mechanism 12.In an embodiment, one or more ports may be split between a plurality ofmechanisms of the device 10. For example, one or more ports may be splitbetween the first mechanism 12 and the second mechanism 14. In such anembodiment, when the internal grooves of the second mechanism aresubstantially aligned with the external grooves of the first mechanism,a number of larger ports equal to the number of grooves on thefirst/second mechanism will be shared by the two mechanisms. In anotherembodiment, when the internal grooves of the second mechanism aresubstantially misaligned with the external grooves of the firstmechanism, a number of smaller ports equal to twice the number ofgrooves on the first/second mechanism will exist. In an embodiment, oneor more ports may be exposed to the exterior of a mechanism of thedevice 10. For example, one or more ports may be exposed to the exteriorof the second mechanism 14. Additional and/or alternate port placementsmay be used within the scope of this disclosure.

Examples of different port and through-hole configurations areillustrated by FIGS. 13A-13J. For example, FIG. 13A illustrates anexemplary second mechanism 14 having four through-holes 1700, 1702,1704, 1706. As illustrated by FIG. 13A, the through-holes may beeccentrically arranged in a radially symmetric manner. Steering cablesmay be delivered through the through-holes.

FIG. 13B illustrates an exemplary second mechanism 14 having threethrough-holes 1708, 1710, 1712 according to an embodiment. Asillustrated by FIG. 13B, the through-holes 1708, 1710, 1712 may bearranged eccentrically in a radially symmetric manner inside thestructure of the second mechanism 14.

FIG. 13C illustrates an exemplary second mechanism 14 having three ports1714, 1716, 1718 contained in an outer wall 1720 of the second mechanism14. The second mechanism 14 may also include one or more through-holessuch as those 1713, 1715, 1717 illustrated by FIG. 13C. In anembodiment, the through-holes 1713, 1715, 1717 may be arrangedeccentrically in a radially symmetric manner. In an embodiment, thethrough-holes may be evenly spaced within the arrangement of the ports1714, 1716, 1718.

FIG. 13D illustrates an exemplary second mechanism 14 having three ports1722, 1724, 1726 located on the exterior of the second mechanism 14.FIG. 13D also illustrates three through-holes 1764, 1766, 1768. In anembodiment, the three through-holes 1764, 1766, 1768 may support threesteering cables. The through-holes 1764, 1766, 1768 may be arrangedeccentrically in a radially symmetric fashion as illustrated by FIG.13D. In an embodiment, the triangle that is formed may include a centerpoint of a cross-section of a mechanism. For example, the triangleformed by the through-holes 1764, 1766, 1768 in FIG. 13D include acenter point 1770 of the second mechanism 14. In an embodiment, thethrough-holes may be arranged as vertices of an equilateral triangle. Inan embodiment, there may exist an even number of through-holes, suchthat each through-hole may have a corresponding through-hole located onthe diametric opposite of a mechanism. In an embodiment, eachthrough-hole and diametrically opposite through hole may oppose eachother.

FIG. 13E illustrates an exemplary second mechanism 14 having two portsarranged eccentrically in a radially asymmetric manner 1728, 1730. Asillustrated by FIG. 13E, the first mechanism 12 may be locatedeccentrically relative to the second mechanism 14. The ports 1728, 1730may be located eccentrically relative to a first mechanism. Asillustrated by FIG. 13E, the ports 1728, 1730 may be completelycontained in the second mechanism 14. As such, no alignment/misalignmentof the first mechanism and the second mechanism 14 may be necessary todefine any plurality of ports 1728, 1730. As illustrated by FIG. 13E,the second mechanism 14 may include one or more through-holes 1727,1729, 1731. The through-holes 1764, 1766, 1768 may be spaced to form atriangle as illustrated by FIG. 12E. In an embodiment, the through-holes1764, 1766, 1768 may be wholly contained in the second mechanism 14.

FIG. 12F illustrates an exemplary first mechanism 12 having a singlethrough-hole 1732 for, as an example, a tensioning cable. In anembodiment, the exemplary first mechanism 12 illustrated by FIG. 12F maycorrespond to the second mechanism 12 illustrated by FIG. 13E. If thethrough-hole is positioned concentrically, it is non-steerable, but islockable when tension is applied. If the through-hole is positionedeccentrically, the first mechanism may be steerable, but not lockable.

FIG. 13G illustrates an exemplary first mechanism 12 having threethrough-holes 1734, 1736, 1738 for, as an example, three steeringcables. In an embodiment, the first mechanism 12 and/or the secondmechanism 14 may be steered with the steering cables. In contrast to asingle through-hole configuration from FIG. 13F, the configurationdepicted in FIG. 13G is both steerable and lockable.

FIG. 13H illustrates exemplary ports 1740, 1742, 1744 defined by a firstmechanism 12 and a second mechanism 14. As illustrated by FIG. 12H, theports 1740, 1742, 1744 may be located on an exterior portion of thefirst mechanism 12 and within the structure of the second mechanism 14.

FIG. 13I illustrates exemplary ports 1746, 1748, 1750 defined by a firstmechanism 12. As illustrated by FIG. 12I, the ports 1746, 1748, 1750 maybe located on an exterior portion of the first mechanism 12. In anembodiment, the first mechanism may have a single through-hole 1747 for,as an example, a tensioning cable.

FIG. 13J illustrates exemplary ports 1758, 1760, 1762 defined by a firstmechanism 12. As illustrated by FIG. 13J, the ports may be located on anexterior portion of the first mechanism 12. The first mechanism 12 mayalso include one or more through-holes 1752, 1754, 1756. Additionaland/or alternate port and through-hole locations may be used within thescope of this disclosure.

In an embodiment, a device 10 having two through-holes eccentricallyarranged in a radially symmetric manner for steering cables may becapable of defining a 2D surface which is planar. In contrast, a device10 having two through-holes for steering cables may be capable ofdefining a 2D surface which is non-planar if the through holes areradially asymmetric. In an embodiment, a device 10 having an odd numberof radially symmetrically or asymmetrically arranged steering cables mayrequire a dedicated actuator for each cable. For example, if a device 10has n steering cables, where n is an odd number, or where n is an evennumber and the holes are arranged in a radially asymmetric fashion, nactuators may be necessary to load the n steering cables. In anembodiment, an actuator may be a device capable of providing a load, aforce and/or the like. Exemplary actuators may include DC motors,stepper motors, EPAM devices, muscles. MicroElectricalMechanical systems(“MEMS”) devices and/or the like.

For example, FIG. 13B illustrates a device 10 having threethrough-holes, each of which may support a steering cable. As the devicein FIG. 13B has an odd number of steering cables (i.e., 3), eachsteering cable may require an actuator.

In an embodiment, a device 10 may have an even number of steering cablesarranged in a radially symmetric manner. In an embodiment, each of thesteering cables may have a corresponding actuator. Alternatively,diametrically opposing pairs of cables may be actuated with a singlecommon actuator. For example, FIG. 13A illustrates a device 10 havingfour through-holes for four steering cables. A first steering cableassociated with a first through-hole (e.g., 1700) may be locatedopposite a second steering cable associated with a second through-hole(e.g., 1704). The first steering cable and the second steering cable maybe considered an opposing pair. In an embodiment, the first steeringcable may be considered a counterpart to the second steering cable. Inan embodiment, the first steering cable and the second steering cablemay be loaded with a single actuator. In an embodiment, the number ofactuators needed to load n steering cables (where n is an even number)may be a number greater than or equal to n and less than or equal to

$\frac{n}{2}$

because each steering cable may have its own actuator or it may share anactuator with an opposing steering cable. An additional actuationelement is necessary to simultaneously apply tension to all cables inorder to lock the mechanism. In such an embodiment the total number ofactuators necessary is

$\frac{n}{2} + 1$

In an embodiment, one or more steering cables may be arranged tomaximize workspace. For devices 10 having an even number of steeringcables, as one steering cable is made longer from the steering process,the length of its counterpart steering cable may be made shorter by anequal amount. For example, referring to FIG. 13A, a first steering cableassociated with a first through-hole (e.g., 1700) may be locatedopposite a second steering cable associated with a second through-hole(e.g., 1704). As the first steering cable is made longer by x amount,the second steering cable may be made shorter by x amount.

While several embodiments of the invention have been described herein byway of example, those skilled in the art will appreciate that variousmodifications, alterations, and adaptations to the described embodimentsmay be realized without departing from the spirit and scope of theinvention defined by the appended claims.

1.-45. (canceled)
 46. An articulated probe device, comprising: a firstmulti-linked mechanism that comprises a passage that extends from aproximal end of the first multi-linked mechanism toward a distal end ofthe first multi-linked mechanism along a longitudinal axis of the firstmulti-linked mechanism; a second multi-linked mechanism thatconcentrically surrounds at least a portion of the first multi-linkedmechanism; one or more steering cables; and an overtube mechanism thatconcentrically surrounds at least a portion of the first multi-linkedmechanism and a portion of the second multi-linked mechanism, theovertube mechanism comprising: a first link positioned at a proximalarea of the overtube mechanism, a plurality of intermediate links,wherein a first one of the intermediate links is movably coupled to thefirst link, a second link which is moveably coupled to a second one ofthe intermediate links and positioned at a distal area of the overtubemechanism, and one or more through-holes that extend along a length ofthe overtube mechanism, wherein the through-holes are configured tosurround at least a portion of the steering cables.
 47. The articulatedprobe device of claim 46, wherein at least one of the first multi-linkedmechanism, the second multi-linked mechanism, and the overtube mechanismis configured to be steerable and extendable beyond the othermechanisms.
 48. The articulated probe of claim 46, wherein at least oneof the steering cables is configured to be terminated at a first end onthe second link of the overtube mechanism and at an end of an actuationcomponent at the proximate area of the overtube mechanism.
 49. Thearticulated probe of claim 48, wherein the steering cable transmitsforce to the second link of the overtube mechanism.
 50. The articulatedprobe of claim 46, wherein the steering cables transmit forces to atleast one of the intermediate links of the overtube mechanism so thatthe overtube mechanism exists in a limp mode when the steering cablesare slack, and so that at least a portion of the overtube mechanismexists in a rigid mode when all the steering cables are under equaltension.
 51. The articulated probe of claim 46, wherein the throughholes are eccentrically arranged in a radially symmetric pattern. 52.The articulated probe of claim 46, wherein the overtube mechanism isconfigured to advance over the first multi-linked mechanism and thesecond multi-linked mechanism when the first multi-linked mechanismoperates in a rigid mode.
 53. The articulated probe of claim 46, whereina radius of curvature of the overtube mechanism is at least as large asa radius of curvature of the second multi-linked mechanism.
 54. Thearticulated probe of claim 46, further comprising a second overtubemechanism configured to surround at least a portion of the overtubemechanism.
 55. The articulated probe of claim 46, wherein each steeringcable is associated with an actuator that is configured to provide aforce to the steering cable.
 56. The articulated probe of claim 46,wherein the first multi-linked mechanism comprises a through-holethrough which is disposed a second steering cable, wherein: a first endof the second steering cable is configured to be terminated on anactuation component at a proximal area of the first multi-linkedmechanism, and a second end of the second steering cable is configuredto be terminated at a link of the first multi-linked mechanism so thatthe second steering cable transmits force to the link of the firstmulti-linked mechanism.
 57. The articulated probe of claim 46, whereinthe second multi-linked mechanism comprises: at least two through-holes;and a plurality of second steering cables, wherein each second steeringcable is positioned to correspond to and pass through one of thethrough-holes of the second multi-linked mechanism.
 58. The articulatedprobe of claim 46, wherein: the first multi-linked mechanism comprisesone or more second through-holes, the second multi-linked mechanismcomprises one or more third through-holes.
 59. The articulated probe ofclaim 58, further comprising: one or more second steering cables; andone or more third steering cables, wherein the one or more secondthrough-holes are configured to surround at least a portion of the oneor more second steering cables, wherein the one or more thirdthrough-holes are configured to surround at least a portion of the oneor more third steering cables.